JPS5919195A - Heat sensitive recording material - Google Patents

Abstract

PURPOSE:To provide a heat sensitive recording material enhanced in the density of saturated color developing due to heating and capable of being reduced in saturated color development temp. obtained by containing benzoyloxy tetramethylpiperizine and bis (tetramethylpiperidyl) sebacate in a color developing layer as sensitizers. CONSTITUTION:To a colorless or light colored color developing dye (e.g., 3-N- cylclohexylamino-6-methyl-7-phenylaminofluorane) and an org. acidic substance (e.g., benzyl-4-hydroxybenzoate), 4-benzoyloxy-2, 2, 6, 6-tetramethylpiperizine) shown by formula and/or bis (2,2,6,6-tetramethyl-4-piperidyl) sebacate shown by formula are added to obtain a composition which is, in turn, dispersed and mixed in an aqueous solution of a water soluble binder such as PVA and the formed suspension is applied to a support such as paper and dried to obtain an objective recording material.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an improvement in the color-forming layer of a heat-sensitive recording material containing a colorless or light-colored color-forming dye and an organic acidic substance that causes the dye to develop color when heated. reached,
Moreover, the present invention provides a heat-sensitive recording material having excellent heat-sensitive performance and having a coloring layer having a high saturated coloring density. That is, the present invention provides a heat-sensitive recording material containing a heat-sensitive coloring layer containing a colorless or light-colored coloring dye and an organic acidic substance, in which the coloring layer contains 4-benzoyloxy-2,2,6,6-titramethylbi, lysine or / and bis(2,2,6,
The present invention is a heat-sensitive recording material characterized in that it also contains 6-deto-poor methyl-4-pyridyl) sepacate.

A heat-sensitive recording material, in particular a color-forming dye that is colorless or light in color (hereinafter referred to as 1 color-forming dye) that develops color upon contact with an electron-accepting substance, and an electron-accepting substance (color developer) that develops the color. Thermal recording paper that uses a color-forming layer consisting of has recently been widely used in facsimiles, and as the speed of the There is a strong demand for the development of

For this reason, higher fatty acid amides have conventionally been widely used as sensitizers for such color-forming systems, and dimethyl terephthalate has also begun to be used as a sensitizer. In addition, the antioxidant bis(3-1g5Rbutyl-5-ethyl-2-hydroxyphenyl)methane has also attracted attention as a substance with sensitizing action, but the present inventors have not yet synthesized these to meet the above requirements. 4-benzo-luoquin-2,2,6,6-titramethylbiperidine and bis(2,2,6,6-tetramethyl-4-piperidine) are known as compounds for preventing photodeterioration of resins. The present invention was completed by discovering that lysyl sebacate exhibits an extremely excellent sensitizing effect in the above-mentioned color-forming system.In other words, when these lysine compounds are added to the above-mentioned color-forming system, they are heated. Another major feature of these two types of hyridine compounds used in the present invention is that, compared to known sensitizing substances, they are able to increase the density of saturated color development and lower the temperature at which saturated color development occurs. In other words, known sensitizing substances require addition of approximately the same amount and viscosity as the color-forming dye used in the color-forming system, but the bi-lysine compound of the present invention has a color-forming dye. 5 parts or 0 parts α for 1 part of dye
．． Addition of 2 parts or less is sufficient. This is not only economically advantageous, but also greatly helps in preventing the phenomenon of "sticking" (peeling of the coating film) caused by the thermal head of a thermal printer.

4-benzoyloxy-2゜2.6 used in the present invention.
6-titramethylpi is lysine (hereinafter referred to as BTMP J) and bis(2,2,6,6-tetramethyl-4
- lysyl) sepacate (hereinafter referred to as "TMP8 J") is a higher fatty acid amide (sensitizer A), bis(3-tert-butyl-5-ethyl-2- The table below shows that it has a superior sensitizing effect compared to hydroxyphenyl)methane (sensitizer B) or dimethyl terephthalate (sensitizer C).

Table 1 shows benzyl-4-hydrogen/benzoate, which is Cζ acidic substance), and chromogenic dye shown in Table 01, 1.
Apply a coating solution containing all the various sensitizers in combination with F [
+Drying 1. 90℃ of the coated surface of the heat-sensitive ML recording paper manufactured by
Table 2 shows a comparison of color density at 6 temperatures of 100°C and 110°C. These two types of heavy machinery acidic substances are those most commonly used as color developers for π°-sensitive paper.

The tllll ti-: values in Table 1 indicate the coloring densities obtained by the experiments described in Examples 1 to 4 and Comparative Examples 1 and 2, and the pl constant values in Table 2 indicate the values.
This shows the experimental coloring efficiency of Samples 5 and 0 and Comparative Examples 3 and 4. The larger the value, the darker the coloring. The filter used for sub-determination was Lattenner 106 for experiment numbers Nll-13 and Nl120-29 (these colors were black), and for experiment numbers 14-19 and Nl130-32 (these colors were black). dark green) and experiment number 63-3
5 (these colors are blue) is Rattenna 25.

Table 1 Organic heavy substances; Benzyl-4-hydroxybe/Shade 5 Sensitizer A to 1.2
4 t27 t286 Increased ∆ cost? 1 B
to 1.21 1
．． 23 t247 Sensitizer 0 10
t19 1.22 1.24 Chromogenic dye = 6-dinitylbutemino-6-methyl-7-phenylaminofluorane 1, ], 1 1.31 1.55 1.3
48BTMP(121,561,38t3B? [1,11321,371,38 1° TMPso, 2 +, 59 1.40
t411 12 Increase/decrease B to
1.23 1.26. t3013 increase *υ1su Oto 1.20 121
+, 22 Chromogenic dye: 6-diethylamino-5-methyl-7-dipendylaminofluora/ (111,311,511,31 14BTMPQ, 2 1.33 137 1375 0.1 1.34 1. 34 1.5416
""" 0.2 t34 1.37 1.
377 18 Sensitizer B to t161
．． 20 1231? Increase 1 [Mllo
1. '0 112 120
1,20 Table 2 Organic acid storage: Bisphenol A Color development ('4 Dye: 5-N-methylcyclohexylamino-6-methyl-7-phenylaminofluorane α1
0.95 1.14 1゜1520BTMP
12 [1,981161,161 0,11051,161,16 22TMPB Q, 2 t
lo 1.17 t176 26 Masabaji JB 1.0
[1B1 1.07 t1127 BT
MP O,21,14t29 t29
28 TMPB α2
t15 1.29 12929 Masuhekoma J plaster A 1.0 19
9 1.16 1.1630 BTM
P α2 1.13 117
t17-31 TMPB O
, 21, 17t29 t2932 jl-Shizuku 81 Warning A 1. o 1
．． 04 1.09 112 Chromogenic dye: Crystal violet lactone 33 BTMP
α2 1.17 L27 12754
TMPEI 0.2 118
1.30 t3065 Sensitizer A
1.0 1.14 120 120 The measured values in these tables indicate that if the piperidine compound of the present invention is used as a sensitizer, color development at a relatively low temperature of 90° to 110°C will result in color development with almost saturated density. These tables clearly show that the concentration is significantly higher than that of other sensitizers.6 It is also clear from these tables that a small amount is sufficient compared to other sensitizers. It's obvious. Experiment No. 1a24 shows that when the amount of other sensitizers, such as sensitizer A, is reduced to the same level as these bi'lysine compounds, the color density is extremely low.

The ratio of biA lysine compound used in the present invention is preferably 1 to t105 to 13 parts per 1 part of the color-forming dye used in the color-forming system, and it is also possible to use Ogaki, but the sensitizing effect increases accordingly. It is uneconomical because almost no sensitizing effect is observed, and if the amount is less than 102 parts, hardly any sensitizing effect is observed. These bi-lysine compounds can be used alone or in combination, and when used, they are pulverized alone and combined with a color-forming dye and an organic acidic substance that have also been pulverized. Alternatively, it may be pulverized with a chromogenic dye or an organic acidic substance. Note that these viridis/compounds can also be used in combination with other types of sensitizers.

The finely pulverized Bi-Lysine compound organic acid substance and color-forming dye are mixed and dispersed in an aqueous solution of a water-soluble binder to form a suspension, which is then coated on paper or a suitable support and dried. A thermosensitive record monthly rate can be produced by.

Examples of the organic acidic substances in the present invention include the above-mentioned bene/ziru-4-hydroxybenzoate and bisphenol A.
In addition, for example, the following compounds can be used, but they are not limited to VJ5. 11-
Phenylphenol, 2-bromo-4-phenylphenol, 4-cyclohegycylphenol, 2-cyclohegycylphenol, 4,4'-hyphenol, 4-human τ
18 cidiphenoxide, methyl-4-hydroxybenzoate, phthyl-4-hydroxybenzoate, hafnal-4-hydroxybenzoate, phenyl-4-hydroxybenzoate, nuclear-substituted benzyl-4-hydroxybenzox-), phenyl gallic acid acid ester, monobenzyl terephthalate, monobenzyl isophthalate,
4-hydroxyacetophenone/, 4-hydroxypropiophenone, 4-hydroxy(/cyphenon, 2,4-
Dihydroxybenzophenone, cylic acid anilide, 2
．． 2'-dihydroxydiphenyl, 4.4'-cyclohexylidene diphenol 4, 41-,,! ethylenediphenol, 4,4'-cyclohexylyanbis(2-ear J'robylphenol), 4-mtertiary octylcatechol, 2,2'-methylene/-bis(4-chlorophenol), 1. 1'-methylene-bis(2-naphthol), 4,4'-5ec-butylidene diphenol, α-naphthol, β-su7thol, bis(4-hydroquinphenyl)sulnoid, 2,2'-bis( 4-
halophenol) sulfyl', 2,2'-bis(4-
halophenol) sulfoxide, 2,2'-his(4-
halophenol) sulfone, 2,4-bis(4-ha-
2-Hydroxyphenyl)-4-methyl Rantane, novolak type phenolic resin.

For example, the following compounds are used as color-forming dyes.
However, it is not limited to these. That is, as a fluoran dye, 3-N-methylcyclohexylamino-6-methyl-7
-phenylaminofluorane, 6-virolidino 6-
Methyl-7-phenylaminofluorane, 3-piperidino-6-methyl-7-phenylaminofluorane, 6-
(N-ethyl-p-methylphenylamino)-6-methyl-7-phenylaminofluorane, 3-(N-ethyl-p-methylphenylamino)-6-methyl-7-p
-methylphenylaminofluorane/, 6-diethylamino-6-methyl-phenylaminofluorane, 3-
diethylamino-6-) f-7-chlorophenylaminofluorane, 3-diethylamino-7-dibenzylaminofluorane, 3-diethylamino-5-methyl-7
-dibenzylaminofluorane, 6-dinitylamino-7-chlorofluorane, 3-diethylamine-6-methyl-7-chlorofluorane, 6-cyclobexylamino-6-chlorofluorane, 3-pyrrolidino-7-di Benzylaminofluoran, 3-pyrrolidino-7-phenylaminofluoran, etc. Lactam dyes include 3.6-bis(diethylamino)fluoran-N-phenyllactam, 3.6-bis(diethylamino)fluoran-N- Triarylmethane dyes such as chlorophenyllactam include 3.3-bis(p-dimethylaminophenyl)-6-dimethylaminophthalide (crystal/siolene tract/), 6-(p-dimethylaminophenyl)- 3-(
Diphenylmethane dyes include 4,4'-bis-diethylaminobenzhydrylbenzyl ether, N-halophenylleucoauramine, and spiro dyes. Monomethyl-spirodinaphthopyran, 3-propyl-
Spiro-dibenzobilane, etc. can be used. Of course, these color-forming dyes can be used alone or in combination of two or more.

Examples of water-soluble binders include polyvinyl alcohol, hydroxyethyl cellulose, carboxymethyl cellulose, styrene-maleic anhydride copolymer salt, styrene-butadiene emulsion, hinyl acetate-maleic anhydride emulsion, polyacrylate, polyacrylamide, Powders, casei/gum arabic, etc. can be used, but are not limited to these.

The above suspension may further contain dispersants (e.g., sodium dioctylsuccinate, sodium dodecylbenzenesulfonate, sodium salts of diuryl alcohol sulfate, fatty acid metal salts, etc.), sensitizers (e.g., bis(tertiary butylphenol)-based compounds], desensitizers (e.g. aliphatic higher alcohols, solid polyhydric alcohols, polyethylene, glycols, guanidine derivatives, etc.), anti-sticking agents (e.g. stearic acid, zinc stearate, calcium stearate, carnauba wax, paraffin wax, ester wax, etc.), fillers (e.g. clay,
talc, kaolin, satin white, titanium oxide, calcium carbonate, magnesium carbonate, barium sulfate, magnesium silicate, aluminum silicate, etc.), antifoaming agents, polymeric light stabilizers, fluorescent brighteners, etc. .

The above suspension is not only used for heat-sensitive recording materials, but also for example,
1-16155, on a conductive layer supported on a support.

By coating and drying, an electrically conductive heat-sensitive RQ recording material can be obtained.

Example 1 Aqueous suspension of organic acidic substance (liquid A), aqueous suspension of color-forming dye (liquid B), aqueous suspension of sensitizer (liquid C), and aqueous filler! ? Four types of suspensions of Jl liquid (D liquid) were prepared as follows.

Solution A: benzyl-4-hydroxybenzony) 1 (L5
p, 41.5 jl of a 15% aqueous solution of polyvinyl alcohol (Kuraray Co., Ltd., [Clacy 105J).

Clay (Engelhard, l'UW-9DJ) a
09 and fine ice 4 a, op together with 1 oop of glass peas were placed in a 250 ml polyethylene bottle, tightly capped, and the Re
(It was attached to a paint container manufactured by i pevt1 and shaken at a vibration frequency of 660 times/min for 8 hours, then the glass beads were removed and an aqueous solution of benzyl-4-hydroxybenzony 1 with a particle size of 2 to 3μ was used. A suspension was obtained.

Solution B: 3-N-methylcyclohexylamino-6-methyl-7-phenylaminofluorane 7,0! , 15% aqueous solution of polyvinyl alcohol (same as above) 41.
5jl, clay (same as above) 11.55' and pure water 4αOP were placed in a 250-sized polyethylene bottle along with Glass Peas 1009, the bottle was tightly capped and shaken with India conditioner at a frequency of 630 times/min for 5 hours. The glass beads were removed to obtain an aqueous suspension of fluoran compound (particle size 2-3μ).

0 liquid: 4-benzoyloxy=2.2,6.6-titramethylopi is lysine (BTMP) 7. Ojl, Polyliquid 4 L5p, Clay (previous verse with myself) 1t5P
Then, 40 g of pure water and 100 IJjl of glass beads were placed in a 25081 polyethylene bottle, and shaken with a sealed paint conditioner at a frequency of 630 times/min for 5 hours, the glass beads were removed and an aqueous suspension of BTMP was prepared. Obtained.

Solution D: 15% water ft-f solution of polyvinyl alcohol (same as above) 4rsy, clay (same as above) 1a5P and pure water 40. The mixture was placed in a 250 ml polyethylene bottle together with Ojl'i Glass Peas 100F, tightly capped, and shaken with a paint conditioner at a vibration frequency of 630 times/min for 5 hours.The glass pieces were then removed to obtain an aqueous clay suspension.

A liquid 10P, B liquid 5. Ojl, O liquid 0.5P and D
A coating solution was prepared by heating and stirring solution 4.59 for 15.20 minutes. Apply the spreading liquid ξ to the white base paper using the wire rod 1
2 and dried at a temperature of 60° C. for 2 minutes to produce thermosensitive recording paper.

Also, instead of the above 0 liquid (lsp and D liquid 4.5P)
Solution top and D solution 4. A thermosensitive recording paper was produced in the same manner using OF.

These thermosensitive recording papers were heated on both sides for 5 seconds at temperatures of 90° C., 100° C., and 110° C. using a dry heat tester (manufactured by Kishino Kagaku Kikai Products Co., Ltd.) to develop color (black). The color density of the colored surface was measured using a Macbeth reflection densitometer model RD-514. The results are shown in Table 1 with experiment numbers N111 and N.
It was shown as a2.゛Example 2 The same organic acidic substance and coloring dye as in Example 1 were used, and bis(2,2,6,6-tetramethyl-4-pilysyl)separate (TMPB) was used as the sensitizer. An experiment was conducted in the same manner as in Example 1.

The results are shown in Table 1 as experiment numbers 3 and 4.

Comparative Example 1 The same 4j organic acidic substance and color-forming dye as in Example 1 were used, and higher fatty acid amide (Nippon Kasei Co., Ltd., [-7mide AP-IJ) (sensitizer A), bis (
An experiment similar to Example 1 was conducted using 3-tertM butyl-5-ethyl-2-hydroxyphenylmethane (jlH[1jB) or dimethyl terephthalate (sensitizer C). The results are shown in Table #11 as experiment number Nn5, column 6, and column 7. In these experiments, 0 solution (aqueous suspension of sensitizer) was mixed with 5. OP was used and no D solution (aqueous suspension of filler) was used.

Example 3 Benzyl-4-hydroxybenzoate and B'rMP were used as the organic acidic substance and sensitizer as in Example 1, and 3-:)ethylamino-6-methyl-7-phenylamine was used as the color-forming dye. An experiment similar to Example 1 was conducted using Tunluora/.

The results are shown in Table 1 as experiment numbers 8 and 9.

Table 1 shows the results of a similar experiment using 6-danitylamino-5-methylfudipendylaminofluoran as a color-forming dye.
It was shown as

Example 4 An experiment similar to Example 3 was conducted using TMPS as a sensitizer and two types of color-forming dyes as in Example 6. The results are shown in Table 1 with experiment numbers N110 and Nα1.
1, No. 16, and No. 17.

Comparative Example 2 An experiment similar to Example 3 was carried out using the same organic acidic substances and color-forming dyes as in Example 3, and using sensitizers B and C as sensitizers (J In these experiments, D solution 5.OP was used, and D solution was not used.These results are shown in Table 1 with the numbers 12, 16, 18, and 19. .

Example 5 As the J-like acidic substance, hisphenol A1 was used as a chromogenic dye, and 1 was 3-N-methylcyclohexylpumino-6-methyl-7-2 enylaminofluorane, and as the sensitizer, BTMP was used. The same experiment as in Example 1 was conducted, and the results are shown in Table 2 with experiment number N1120 and koji 21.
It was shown as

The results of a similar experiment using TMPS as a sensitizer are also shown as experiment numbers 22 and 23.

Comparative Example 3 The results of an experiment similar to Example 5 using Sensitizer A and Sensitizer B are shown in Table 2 with experiment number N1.
24, N125 and m26. At this time, in experiment number 24, liquid C toP and liquid D 4. For N125 and N126, use D solution 5. Op was used and Solution D was not used.

Example 6 An experiment similar to Example 1 was conducted using bisphenol A as the organic acidic substance, 6-diethylamino-6-methyl-phenylaminofluoran as the color-forming dye, and BTMP or TMPS as the sensitizer. The results are shown in Table 2 as experiment numbers 27 and 1lla28.

Table 2 shows the results of a similar experiment using 3-:)ethylamino-5-methyl-7-:)benzylaminofluoran as the color-forming dye and BTMP or TMPS as the sensitizer. The experiment numbers were shown as ug60 and m31.

The results of experiments conducted in the same manner as above using crystal violet lactone as the color-forming dye and using two types of sensitizers are shown as experiment numbers Ugly 36 and Ugly 34.

Comparative Example 4 Bisphenol A was used as the 41-organic acidic substance, Sensitizer A was used as the sensitizer, and 3-:)ethylamino-6-methyl-7-phenylaminofluorane, 3-diethylamino- The results of an experiment similar to Example 1 using crystal violet lactone coated with 5-methyl-7-dipendylaminoflumelan are shown in Table 2 as experiment numbers Na29, m32, and Na35. For these experiments, an aqueous N% suspension of sensitizer A was used.
．． O2 was used, and the D solution was almost used.

Claims (1)

[Claims] In a heat-sensitive recording material having a heat-sensitive coloring layer containing a colorless or light-colored coloring dye and an organic acidic substance, the coloring layer contains 4-benzoyloxy-2゜2.6.6-titramethylpiveridine or/and A heat-sensitive recording material characterized in that it also contains bis(2,2,6,6-tetramethyl-4-piperidyl)sepacate.